Alternative Endings of the Gospel of Mark in (Relatively) Early Egyptian Manuscripts

I happen to be looking at 'the Coptic Version of the New Testament' and I noticed something that Mr. Snapp might be able to explain. Is it well known that in A and E1 there is a reference to an alternative ending which reads as follows:

In A at the end of verse 8 in the break as if referring to the last 12 verses is a gloss:


this is the chapter expelled in the Greek.


In the margin written by the ordinary corrector


And all the things which he ordered to them who came after Peter (lit. and) openly they spake of them. And after these (things) indeed, Jesus appeared to them from the risings of (the) sun until his setting and he sent them to preach (lit. throw) (the) good tidings, holy, imperishable, of the eternal life. Amen. These (words) themselves are belonging to those: (viz) And after these (things) troubles and perplexities seized them: and they said not a word to anybody for they were fearing.


In E1 after verse 8 is a break which marks the end of verses in all MSS and in it a sign corresponding to two similar signs in the margins which seem to indicate an omitted section then in the lower margins is written by the original hand:


In another writing: and all the things they ordered Peter, he did them quickly. And after these (things) Jesus manifest himself to them from the risings of (the) sun until his settings: by them he sent the preaching, holy, unpolluted, for (lit in) eternal salvation. This section is translated thus (in Arabic):


And all things which he ordered to Peter, they did them decidedly (decisively) : and after this Jesus appeared to them from the risings of the sun to her settings, and by their means, he sent the Gospel, pure (holy), without pollution.